1. Field of the Invention
The present invention relates to a method of manufacturing a semiconductor device including a process of processing a substrate in a process chamber, a method of processing a substrate, and a substrate processing apparatus preferably used in the process.
2. Description of the Related Art
As new random access memories (RAMs) that can be substituted for dynamic random access memories (DRAMs), for example, a capacitor-less DRAM using a silicon on insulator (SOI) substrate (SOI-type RAM), a magneto-resistive RAM (MRAM), a phase change RAM (PRAM), a resistive RAM (ReRAM), and so on, may be exemplified.
Among these, the ReRAM has a capacitor structure in which a thin film formed of a transition metal oxide (hereinafter, a transition metal oxide film) is disposed between metal electrodes, and uses variation in resistance of the transition metal oxide film generated by applying a voltage between the metal electrodes (variation in electric field induction resistance) as memory information. Since the ReRAM has a low consumption power of 1/1000 or less per one bit, compared to that of a conventional NOR-type flash memory, and a read-out time and a re-writing time, both of which are a high speed of about 10 ns, the ReRAM is receiving attention as a next-generation non-volatile memory.
In the ReRAM, a tantalum oxide-based film such as a tantalum oxide (TaOx) film is used as a transition metal oxide film to enable control of an oxygen concentration in a film. In a development step of a ReRAM device, a method of forming a tantalum oxide film is mainly performed by a physical vapor deposition (PVD) method. However, since the transition metal oxide film requires high step coverage due to a structure of the ReRAM, the PVD method cannot be easily applied to mass production.